Copying apparatus

ABSTRACT

A copying apparatus in which thin or thick originals such as individual sheets or thick books are selectively driven over an illumination slit aperture, characterized by a transparent book support such as a glass plate connected to a known transport mechanism for individual sheets such as a pair of transport rolls. The book support is located on the extension of the transport mechanism, and the transport mechanism and the book support are selectively movable together.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a copying apparatus in which two- orthree-dimensional originals such as individual sheets or thick books areselectively driven over an illumination slit aperture.

2. Description of the Prior Art

In the copying apparatus of the described type, the slit aperture isprojected, for example, on a drum carrying photosensitive paper thereon.The speed of rotation of the drum is made equal to the speed at whichthe originals are moved over the slit aperture. The images of theoriginals guided over the slit aperture are successively exposed ontothe photosensitive paper on the drum. Thereafter, the photosensitivepaper can be developed in a subsequent developing device in a knownmanner.

Such a copying apparatus has an advantage that both individual sheetsand desired book pages can be copied. However, the operation of suchapparatus is troublesome because the original is usually placed on aglass plate which is movable over the slit aperture, which glass platemust be covered in order not to dazzle the user. Accordingly, toposition the original, a cover or a flap cover must first be opened sothat the original can be placed on the glass plate, whereafter the coveror the flap cover must be shut again. The same procedures are requiredto remove the original. In addition, the original must be placed withina predetermined field on the glass plate in accordance with its size, sothat copying with such apparatus is troublesome and time-consuming.

There is also known a device in which the originals, when they areindividual sheets, are directly inserted into a guide groove in thedevice and gripped by transport rolls so as to move through the device.In this case, one can successively introduce individual sheets asoriginals into the device, thereby enabling quick and simple copying totake place. However, this device does not permit copies of books to beobtained.

Accordingly, it has already been proposed that for copies of individualsheets, two sets of transport rolls be used to guide the sheets over theillumination slit aperture and that for copies of desired book pages,the upper rolls of the transport mechanism for individual sheets bedetachably arranged and a glass plate with a book resting thereon beguided by utilizing the remaining lower transport rolls of the transportmechanism. The remaining lower transport rolls are frictionallyengageable with the glass plate to ensure the automatic transportthereof.

This arrangement has the disadvantages that, to obtain copies of books,part of the apparatus must be detached to change the constructionthereof and, moreover, the detached apparatus part must be placedsomewhere else during copying.

SUMMARY OF THE INVENTION

The object of the invention is to provide a novel copying apparatuswhich enables both two-dimensional and three-dimensional originals suchas individual sheets or book pages to be copied without changing thearrangement of the apparatus in any way while maintaining simplicity andquickness of the copying, and particularly permits individual sheetsused as originals, to be continuously introduced into the apparatus.

Such object of the present invention can be achieved by a copyingapparatus of the type described at the beginnning hereof in which atransparent book support, preferably in the form of a glass plate, isconnected to a known transport mechanism for individual sheets,preferably in the form of a pair of transport rolls, the book supportbeing located on the extension of the transport mechanism for individualsheets, and the transport mechanism for individual sheets and the booksupport being selectively movable together.

According to the construction of the present invention, individualsheets are guided for copying to the transport rolls, which move thesheets to pass over the illumination slit aperture. Thus it is possibleto introduce the successive sheets continuously into the apparatus as inthe aforesaid known system. In this case, the transport mechanism andthe book support remain stationary in their positions.

When certain pages of a book are to be copied, the book is opened andplaced on the glass plate, then the transport mechanism for individualsheets is moved together with the book support so that the glass platewith the book thereon is guided over the illumination slit aperture.

In a preferred embodiment of the present invention, the book support canalso serve as guide to insert individual sheets into a first set oftransport rolls.

The common movement of the transport mechanism and the book support canbe accomplished mechanically. However, such construction requires anadditional cost, so that in a preferred embodiment of the presentinvention, therefore, the book support and the transport mechanism forindividual sheets are arranged so as to be manually movable.

In this case, care must be taken so that the speed of such movement maybe in accord with the speed of rotation of the drum, for example,because the image of the original would otherwise be distorted. In orderto achieve this, according to another preferred embodiment of thepresent invention, the transport mechanism for individual sheets isdesigned so that it is driven by a motor which in turn acts as a brakingdevice for limiting the speed of the book support which is manuallymovable.

In the construction of this preferred embodiment, operation is effectedas follows: If the book support is moved too fast, a free wheel willform a rigid connection between the book support and a chain driven bythe drive motor when a predetermined limit speed is reached. In otherwords, if this limit speed is exceeded, the motor will brake thepressure manually applied to the book support. This brake force isclearly sensed by the user so that it becomes very easy for the user toexactly maintain the limit speed determined by the motor when hedisplaces the book support. Conversely, when the user displaces the booksupport too slowly, he can also sense the drop of the speed because of adrop in the braking resistance.

The free-wheel arrangement has the advantage that the book support aftercopying can be brought back to its start position without any restraint.

The drive motor for the free wheel may advantageously be used to drivethe transport mechanism for individual sheets via the chain. Therefore,it is possible to move the image-receiving drum, the transport mechanismfor individual sheets and the free wheel for moving the book support insynchronism. Conveniently, the chain of the drive motor for driving thetransport mechanism for individual sheets may be engaged with the drivegear of the free wheel at the same time.

Preferably, the shaft for the free wheel is fixedly mounted to the booksupport.

According to still another embodiment of the present invention, theaforesaid free wheel may be replaced by a coupling. With the aid of thiscoupling, automatic movement of the book support can be effected. Indecoupled position, individual sheets are copied and the return of thebook support is accomplished manually.

The book support and the transport mechanism for individual sheets areheld in a start position by lock means which preferably function underthe action of a spring. A smaller manual pressure on the book supportwill suffice to permit movement of the book carrier.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in detail with respect to embodimentsshown in the accompanying drawings, in which:

FIG. 1 is a schematic view, in longitudinal section, of the copyingapparatus; and

FIG. 2 is a partly cut-away side view of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Individual sheets to be copied are inserted between a pair of transportrolls 1 from above a glass plate 2. The transport rolls 1 guide theinserted individual sheets over another glass plate 3 to another pair oftransport rolls 4, which discharges the originals passed through thetransport unit 1, 3, 4 onto a table 5. In the position shown in FIG. 1,the image of the original which moves over the glass plate 3 isprojected through a mirror 6, an objective lens 7 and a mirror 8disposed just behind the objective lens onto a segment A of a drum 9.The illumination of the glass plate 3 and, accordingly, of the originalis carried out by two light sources 10 and 11, to which mirrors 12 and13 are disposed to correspond.

The drum 9 is rotatable in the direction of arrow 14. The drum 9 isdriven by a motor 15 for driving a chain 16 as shown in FIG. 2. Thechain 16 is engaged with a gear 18 of the drum and moves in thedirection of arrow 17. The chain 16 is further engaged and guided by areadily braked gear 19 fixedly positioned and rotatably mounted in theapparatus. As will be described, along the path of the chain 16, thereare further disposed a gear 20 of a free wheel clutch device 21, atension wheel 22 and a gear 23, via which the chain is guided in thedirection of arrow 24. An unshown deflection gear then brings the chain16 back to the gear 18 of the drum 9, thus driving it in an endlessmanner. In order to equalize the speed of rotation of the drum 9 to thatof movement of the original between the transport rolls 1 and 4, thegear 23 is connected to another gear 25 mounted on the same shaft. Thisgear meshes with a gear 26. The gear 26 is mounted on the shaft whichcarries the lower one of the set of transport rolls 1, so as to rotatethat particular roll at a reduced speed selected to equal the speed ofrotation of the drum 9. Mounted on the shaft of the gear 26 is anothergear 27 which is engaged via a chain 28 with a gear 29 for rotating thelower one of another set of transport rolls 4. Thus, the transport rolls4 at the outlet side are rotated at the same rotational speed as thetransport rolls 1 at the inlet side.

In order to permit the inserted individual sheets to move over the glassplate 3 without hindrance, the edge 30 of the glass plate 3 adjacent tothe inlet side is downwardly inclined. The transport unit 1, 3, 4,including the first glass plate 2, is housed in a casing 31. The casing31, having the glass plate 2, transport unit 1, 3, 4 and table 5, isreciprocally movable on a roll track 33 fixedly provided in theapparatus, in the direction of arrow 34. During the movement of thecasing, the gears 20, 22 and 23 move on the chain 16.

To copy desired pages of a thick book 35, it is opened at the pages tobe copied and placed on the glass plate 2. Then the book is guided overthe illumination slit aperture 36 so that the images of the pages to becopied are projected on the drum 9. In the start position shown in FIG.1, a lever 37 pivotable about the shaft 36' has its projection 38received in a corresponding groove 39 formed in the casing 31 so thatthe casing 31 is held in its start position. The movement of the glassplate 2 and the aforesaid transport unit connected thereto is carriedout by manually .Iadd.pushing the glass plate .Iaddend.in the directionof arrow 40. The lever 37 is under the action of a spring 41 so that theprojection 38 of the lever is disengaged from the groove 39 simply bypushing the plate slightly.

The free wheel 21 has a shaft 50 fixedly mounted in the casing 31, andon the shaft 50 is seated a wheel 51 which carries the gear 20. Thewheel 51 has progressively enlarged cut-outs 52 in which balls 53 arereceived respectively.

When the glass plate 2 is at rest, the gear 20 is continuously rotatedby the moving chain 16. The balls 53 are then in abutment with thewidest end portions of the cut-outs so that no rotational movement isapplied to the shaft 50. When the glass plate 2 is moved in thedirection of arrow 40, the condition described above is maintained aslong as the speed of movement of the glass plate is lower than the speedof movement of the chain 16. If the speed of movement of the glass plate2 reaches the speed level of the chain 16, then the balls 53 are pressedto go toward the narrower ends of the cut-outs 52, thereby creating arigid connection between the wheels 51 and 50. As the result of such arigid connection therebetween, the glass plate 2 can not move in thedirection of arrow 40 faster than the speed of movement of the chain 16.Thus a braking force is applied at the synchronous speed of the drum 9and casing 31.

According to the arrangement described above, it is ensured that theglass plate 2 be moved exactly in synchronism with the speed of rotationof the drum 9. When the glass plate 2 with a book thereon is guided overthe illumination slit aperture 36 and copying has been completed, theplate 2 can be returned to its start position without any difficulty.During this return movement, the free wheel imparts no brake force tosuch return motion, because the balls 53 are now again positioned towardthe widest end portions of the cut-outs 52.

We claim:
 1. Photocopying apparatus comprising a housing, exposure slitmeans fixedly mounted on said housing, a transparent support member forreceiving thereon a thick original to be copied, sheet originaltransporting means including at least one pair of opposed rollersoperable to move a sheet original past said exposure slit means, acasing movably mounted on said housing and having said support memberand sheet original .Iadd.transporting means .Iaddend.fixedly connectedthereto wherein said support member can be moved past said exposure slitmeans, means for releasably holding said casing in a fixed positionwhile said sheet original transporting means operates to move a sheetoriginal past said exposure slit means and for releasing said casing forsaid movement on said housing when a thick original is to be copied,driving means coupled to one of said opposed rollers to impartrotational movement thereto, and clutch means mounted on said casing andcoupled to said driving means for allowing said casing to remain in saidfixed position while a sheet original is being copied and to maintainthe speed of movement of said casing in synchronism with the speed ofmovement of said driving means when a thick original is being copied. 2.Photocopying apparatus according to claim 1, wherein said clutch meanscomprises a shaft fixedly mounted to said casing and means engaging saiddriving means for free rotation only in one direction with respect tosaid shaft and being fixed with respect to said shaft to stop therotation thereof when said casing is moved to copy a thick original. 3.Photocopying apparatus according to claim 2, wherein said driving meansincludes a chain, and wherein said engaging means comprises a wheelprovided to be rotatable around said fixed shaft and having teeth forengaging said chain, said wheel having a plurality of circumferentiallyextending openings communicating with said shaft and each said openingbeing tapered at its outer periphery to provide a wide portion and anarrow portion, and a plurality of balls respectively received in saidopenings to be rotatable at said wide portion while confined to fix saidwheel to said shaft at said narrow portion.
 4. Photocopying apparatusaccording to claim 2, wherein said engaging means includes a wheelmounted on said shaft and provided with a gear, and wherein said drivingmeans comprises a chain in mesh with said gear.
 5. Photocopyingapparatus according to claim 1, wherein said casing is mounted for beingmanually returned to its said fixed position after completion of itsmovement.
 6. Photocopying apparatus according to claim 1, wherein saidtransparent support member for said thick original is mounted to providea guide member for a sheet original inserted into said sheet originaltransporting means.
 7. Photocopying apparatus according to claim 1,wherein said means for releasably holding said casing comprises aprojecting member resiliently mounted on said housing, and wherein saidcasing defines a recessed area for releasably receiving said projectingmember. .Iadd.
 8. Photocopying apparatus selectively operable in a firstmode for copying relatively thick originals and in a second mode forcopying sheet originals, comprising an exposure station through which anoriginal to be copied is to be moved, an optical system for projectingan image of an original moving through said exposure station to animaging station, means for moving a photosensitive member through saidimaging station for the formation of an image of said original thereon,a support carriage capable of supporting relatively thick originals,means for permitting said carriage to be moved along a path such as tocarry such originals through said exposure station when the apparatus isoperated in the first mode, a sheet conveyor operable to transport sheetoriginals through said exposure station while said carriage isstationary when the apparatus is operated in the second mode, said sheetconveyor being mounted in tandem with said support carriage and beingmovable therewith when the apparatus is operated in the first mode, andan endless flexible transmission member engaged with said sheet conveyorfor transmitting drive thereto, said transmission member including aportion which extends along said path of movement of said carriage sothat, during operation of the apparatus in the first mode, saidtransmission member remains in engagement with said sheet conveyor..Iaddend..Iadd.
 9. Apparatus according to claim 8, wherein saidtransmission member is a chain. .Iaddend..Iadd.
 10. Apparatus accordingto claim 8, wherein said sheet conveyor comprises a pair of transportrollers driven by said transmission member. .Iaddend..Iadd. 11.Apparatus according to claim 10, wherein said transmission member is achain and said sheet conveyor includes a gear wheel engaged with saidchain, and means connecting said gear wheel to said transport rollers sothat said transport rollers are driven by said chain via said gearwheel. .Iaddend..Iadd.
 12. Apparatus according to claim 8, wherein saidsupport carriage is arranged to be moved along said path by manualforce. .Iaddend..Iadd.
 13. Apparatus according to claim 12, includingcoupling means coupling said carriage to said transmission member sothat, when said carriage is moved to carry an original through saidexposure station during copying in said first mode, the carriage isprevented from being moved faster than said transmission member..Iaddend. .Iadd.
 14. Apparatus according to claim 13, wherein saidcoupling means comprises a freewheel device. .Iaddend..Iadd. 15.Apparatus according to claim 14, wherein said transmission member is achain and said coupling means includes a gear engaged with said chainand coupling said chain to said freewheel device. .Iaddend..Iadd. 16.Apparatus according to claim 15, including a motor arranged to drivesaid transmission member and to provide a resistance to movement of thecarriage at a speed faster than the speed at which the transmissionmember is driven by the motor, when the carriage is manually movedduring copying in the first mode. .Iaddend. .Iadd.
 17. Apparatusaccording to claim 8, including means for providing a driving force tosaid carriage for moving said carriage during operation of the apparatusin the first mode. .Iaddend..Iadd.
 18. Apparatus according to claim 17,including coupling means for selectively coupling said carriage to saidtransmission member for the application of said driving force to saidcarriage, via said transmission member, when the apparatus is operatedin the first mode. .Iaddend..Iadd.
 19. Apparatus according to claim 18,wherein said coupling means is arranged so that said driving force maybe applied to said carriage only in the direction in which the carriageis moved during exposure of an original carried thereby, said carriagebeing arranged to be manually moved in the opposite direction for returnto a rest position. .Iaddend..Iadd.
 20. Apparatus according to claim 8,wherein said transmission member is also coupled to said means formoving a photosensitive member for effecting operation thereof..Iaddend..Iadd.
 21. Apparatus according to claim 8, including a lockmechanism for maintaining said carriage in a stationary position duringoperation of the apparatus in the second mode. .Iaddend..Iadd. 22.Apparatus according to claim 21, wherein said lock mechanism comprises amember biassed into locking engagement with said carriage but arrangedto become disengaged therefrom when a force is applied to the carriagefor effecting movement thereof. .Iaddend. .Iadd.
 23. Apparatus accordingto claim 8, wherein said sheet conveyor is arranged so that sheetoriginals may be guided thereinto by using an original support surfaceof said carriage as a guide surface. .Iaddend..Iadd.
 24. Photocopyingapparatus selectively operable in a first mode for copying relativelythick originals and in a second mode for copying sheet originals,comprising an exposure station through which an original to be copied isto be moved, an optical system for projecting an image of an originalmoving through said exposure station to an imaging station, means formoving a drum adapted to carry a photosensitive member through saidimaging station for the formation of an image of said original thereon,a support carriage capable of supporting relatively thick originals,means for permitting said carriage to be moved along a path such as tocarry such originals through said exposure station when the apparatus isoperated in the first mode, a sheet conveyor operable to transport sheetoriginals through said exposure station while said carriage isstationary when the apparatus is operated in the second mode, said sheetconveyor being mounted in tandem with said support carriage and beingmovable therewith when the apparatus is operated in the first mode, anda transmission means engaged with said sheet conveyor for driving samewhile allowing said casing to remain stationary when said apparatus isoperated in said second mode and to maintain the speed of movement ofsaid casing in synchronism with the speed of movement of saidphotosensitive member during operation of said apparatus in the firstmode, said transmission means remaining in engagement with said sheetconveyor during operation of the apparatus in said first mode. .Iaddend.